Giltman is having a sale on sigg water bottles. I know there are many more lightweight options out there, but for daily use these work great.

http://www.giltman.com/invite/zeroforhire

full disclosure... I get a $25 credit when you place your first order. If you do not want to support my gear addiction, you can request an invite on their site... but it may take awhile for you to get accepted.